(1) Field of Invention
The airlift pump device described herein relates generally to the recovery of subsurface liquid or semi-liquid material, and specifically to an airlift pump having a streamlined surface for repeated insertion into and removal from narrow groundwater monitoring wells without entanglement.
(2) Background
An airlift pump generally comprises a hollow, cylindrical main body connected to a drainage conduit. The main body is submerged into a subsurface liquid or semi-liquid material, causing the interior of the main body to fill with such material. A gas, such as air, is then introduced into the main body, thereby reducing the specific gravity of the material in the upper part of the main body, which causes that material to become buoyant. As the buoyant material moves upward toward the ground surface, additional liquid material is drawn into the bottom end of the main body, causing a continuous pumping action.
The present device comprises an improved airlift pump for use in the groundwater monitoring industry. This industry uses standard monitoring wells having a relatively small diameter, and prior airlift pumps were difficult, if not impossible, to operate in such tight confines. In addition, operation of prior airlift pumps required expensive customized equipment because these pumps could not accommodate the hoses, fittings, and other pumping equipment standard in the industry.
The device disclosed herein seeks to overcome these problems by providing an improved airlift pump comprising features that optimize performance in the confines of narrow wells. The simplified features and operation of the device permit a significant cost savings over the current pumping methods.